Influence Of MiRNA-206on Tamoxifen Sensitivity Of ERα Positive Breast Cancer Cells

OBJECTIVE: To investigate the influence of mir-206on the expression level ofestrogen receptor α and the sensitivity of tamoxifen of ERα positive breast cancercells.METHODS: Expression of mir-206and ERα mRNA of breast cancer cellsMCF-7was quantitated by RT PCR; the change of expression of mir-206and ERαmRNA was quantitated after MCF-7cells were transfected by mir-206mimic,inhibitor and corresponding negative controls for24h; cell growth was measured byutilizing MTT after transfected MCF-7cells were treated with5ug/ml tamoxifen for24h.RESULTS：Introduction to MCF-7cells with mir-206mimic decreased ERαmRNA expression but had no notably effect on cell growth with tamoxifen (t=2.252，P=0.0544), while introduction with mir-206inhibitor increased ERα mRNAexpression and MCF-7cells were more sensitive to tamoxifen (t=4.856，P=0.0013).CONCLUSIONS: Inhibition of miR-206increases the sensitivity of tamoxifenof ERα positive breast cancer cells.